package com.zwx.helloworld.pub.util;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;
/**
 * Jackson 工具类
 * <p>Title: JsonUtils</p>
 * <p>Description: </p>
 *
 * @author weixin.zhu
 * @version 1.0.0
 * @date 2022/2/17 21:50
 */
public class JsonUtils {


	    private final static ObjectMapper objectMapper = new ObjectMapper();

	    public static ObjectMapper getInstance() {
	        return objectMapper;
	    }

	    /**
	     * 转换为 JSON 字符串
	     *
	     * @param obj
	     * @return
	     * @throws Exception
	     */
	    public static String obj2json(Object obj) throws Exception {
	        return objectMapper.writeValueAsString(obj);
	    }

	    /**
	     * 转换为 JSON 字符串，忽略空值
	     *
	     * @param obj
	     * @return
	     * @throws Exception
	     */
	    public static String obj2jsonIgnoreNull(Object obj) throws Exception {
	        ObjectMapper mapper = new ObjectMapper();
	        mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
	        return mapper.writeValueAsString(obj);
	    }

	    /**
	     * 转换为 JavaBean
	     *
	     * @param jsonString
	     * @param clazz
	     * @return
	     * @throws Exception
	     */
	    public static <T> T json2pojo(String jsonString, Class<T> clazz) throws Exception {
	        objectMapper.configure(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY, true);
	        return objectMapper.readValue(jsonString, clazz);
	    }

	    /**
	     * 字符串转换为 Map<String, Object>
	     *
	     * @param jsonString
	     * @return
	     * @throws Exception
	     */
	    @SuppressWarnings("unchecked")
		public static <T> Map<String, Object> json2map(String jsonString) throws Exception {
	        ObjectMapper mapper = new ObjectMapper();
	        mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
	        return mapper.readValue(jsonString, Map.class);
	    }

	    /**
	     * 深度转换 JSON 成 Map
	     *
	     * @param json
	     * @return
	     */
	    public static Map<String, Object> json2mapDeeply(String json) throws Exception {
	        return json2MapRecursion(json, objectMapper);
	    }

	    /**
	     * 把 JSON 解析成 List，如果 List 内部的元素存在 jsonString，继续解析
	     *
	     * @param json
	     * @param mapper 解析工具
	     * @return
	     * @throws Exception
	     */
	    private static List<Object> json2ListRecursion(String json, ObjectMapper mapper) throws Exception {
	        if (json == null) {
	            return null;
	        }

	        List<Object> list = mapper.readValue(json, List.class);

	        for (Object obj : list) {
	            if (obj != null && obj instanceof String) {
	                String str = (String) obj;
	                if (str.startsWith("[")) {
	                    obj = json2ListRecursion(str, mapper);
	                } else if (obj.toString().startsWith("{")) {
	                    obj = json2MapRecursion(str, mapper);
	                }
	            }
	        }

	        return list;
	    }

	    /**
	     * 把 JSON 解析成 Map，如果 Map 内部的 Value 存在 jsonString，继续解析
	     *
	     * @param json
	     * @param mapper
	     * @return
	     * @throws Exception
	     */
	    private static Map<String, Object> json2MapRecursion(String json, ObjectMapper mapper) throws Exception {
	        if (json == null) {
	            return null;
	        }

	        Map<String, Object> map = mapper.readValue(json, Map.class);

	        for (Map.Entry<String, Object> entry : map.entrySet()) {
	            Object obj = entry.getValue();
	            if (obj != null && obj instanceof String) {
	                String str = ((String) obj);

	                if (str.startsWith("[")) {
	                    List<?> list = json2ListRecursion(str, mapper);
	                    map.put(entry.getKey(), list);
	                } else if (str.startsWith("{")) {
	                    Map<String, Object> mapRecursion = json2MapRecursion(str, mapper);
	                    map.put(entry.getKey(), mapRecursion);
	                }
	            }
	        }

	        return map;
	    }

	    /**
	     * 将 JSON 数组转换为集合
	     *
	     * @param jsonArrayStr
	     * @param clazz
	     * @return
	     * @throws Exception
	     */
	    public static <T> List<T> json2list(String jsonArrayStr, Class<T> clazz) throws Exception {
	        JavaType javaType = getCollectionType(ArrayList.class, clazz);
	        List<T> list = (List<T>) objectMapper.readValue(jsonArrayStr, javaType);
	        return list;
	    }


	    /**
	     * 获取泛型的 Collection Type
	     *
	     * @param collectionClass 泛型的Collection
	     * @param elementClasses  元素类
	     * @return JavaType Java类型
	     * @since 1.0
	     */
	    public static JavaType getCollectionType(Class<?> collectionClass, Class<?>... elementClasses) {
	        return objectMapper.getTypeFactory().constructParametricType(collectionClass, elementClasses);
	    }

	    /**
	     * 将 Map 转换为 JavaBean
	     *
	     * @param map
	     * @param clazz
	     * @return
	     */
	    public static <T> T map2pojo(Map map, Class<T> clazz) {
	        return objectMapper.convertValue(map, clazz);
	    }

	    /**
	     * 将 Map 转换为 JSON
	     *
	     * @param map
	     * @return
	     */
	    public static String mapToJson(Map map) {
	        try {
	            return objectMapper.writeValueAsString(map);
	        } catch (Exception e) {
	            e.printStackTrace();
	        }
	        return "";
	    }

	    /**
	     * 将 JSON 对象转换为 JavaBean
	     *
	     * @param obj
	     * @param clazz
	     * @return
	     */
	    public static <T> T obj2pojo(Object obj, Class<T> clazz) {
	        return objectMapper.convertValue(obj, clazz);
	    }
	}